I have a client who needs the following scenario:
- Many users, potentially thousands or tens of thousands, will sign up
to receive a daily DM from the client's site. With a limit of 250 DMs
per day, the client wants to use each user's account to send a DM to
that user.

- These users will give the app permission to send DMs to their
account through OAuth.
- The app will use each user's OAuth credentials to send 1 DM to that
user each day.
So, John signs up and allows DMs with OAuth. John's OAuth tokens are
used to have John's account send a DM to John.
Question 1: Is it technically possible to send a DM to @john using the
OAuth tokens for @john.
Question 2: Is this model limited to 250 DMs per day? If the answer to
question 1 is yes, it seems that this is really just 1 DM per account
per day. Is this true, or is the app's account used to total up the
DMs for the limit.
Answer to expected comments: yes, I know the client could use email.
They want to use DMs. They want this to be a Twitter system and feel
that DMs let them stay within Twitter.
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